This one wasn't pretty, but Bayer won't care after coming away from Borussia-Park with a well-executed 1-0 win.
Prior to this game, Gladbach and Leverkusen had shared a mammoth 25 goals in their last six meetings. Goal-mouth action and dodgy defending have almost become synonymous with this fixture, and yet if someone had cordoned off each penalty area before the game, it's not really all that likely that anyone would have even noticed for a good long while.
The first half was played almost entirely in the middle third. Gladbach, in desperate need to brush aside some mid-season blues - they went into this game without a win since the winter break - pushed high up the pitch and pressed with energy. Though it would be fair to say that their performance erred closer to the 'perspiration' end of the scale than the 'inspiration'.
Bayer were safety entrenched in their defensive lines and looked to break quickly down the flanks. Patrick Herrmann stung the palms of Bernd Leno with a well-sruck volley, but that was just about as good as it got for hosts in the first half. With space denied to them, there simply wasn't sufficient guile or confidence to produce a final pass of telling quality.
Not that Leverkusen were the epitome of attacking fluidity either, of course, though they did offer greater penetration when they got the ball forward quickly enough. Stefan Kießling's influence slowly grew and Son Heung-min was the main beneficiary, becoming the sole recipient of what little space there appeared to be on the pitch. He failed to really use it effectively, but the warning signs were there.
The second half, whilst never threatening to purr into life, was a more watchable affair. It was almost as if the coaches and both sets of players had got their heads together during the break and agreed that there had to be more to life than this.
Both teams dropped their defensive lines a little deeper, which opened up the midfield to a far greater extent. Gladbach, whose need for a win was more pressing, required more space if they were to craft something, but it was the visitors who made better use of it.
They came out of the traps quicker and Emre Can should have done better with a far post header, but there was nothing disappointing about Son's brilliant matchwinner. The Korean collected a pass from Sidney Sam before thwacking a sumptuous swerving strike into the far corner. It was a little oasis of joy is desert of drudgery.
Gladbach responded, as you'd expect them to, but it was just a slightly more urgent version of the rubbish that preceded it. They pressed the box and, in fairness, did create good shooting opportunities. They were either straight down the throat of a grateful Leno or high, wide and about as handsome as a fat pigeon gorging on discarded profiterole, with the usually talented left foot of Jaun Arango a surprising culprit.
It is perhaps too easy to criticise Die Fohlen too much, though. What we saw here was a consumate away performance from Sami Hyypia's men. They defended in numbers and broke with a little incision. As the game become more stretched after Son's brilliant strike, it was still Bayer who looked more likely to add to the scoring, with Kießling pulling one great chance in particular wide.
In the grand old scheme of things, Gladbach just about got what their lack of quality deserved.
Borussia Monchengladbach: Ter Stegen, Nordtveit, Jantschke, Stranzl, Wendt, Kramer, Xhaka (Younes 83'), Herrmann (Hrgota 67'), Arango (Mlapa 83'), Raffael, Kruse
Bayer Leverkusen: Leno, Hilbert, Toprak, Spahic, Can, Bender, Rolfes, Castro, Sam (Derdiyok 69'), Kießling (Wollscheid 90'), Son (Hegeler 81')
Goals: Son (67)